diff --git a/src/GF/Grammar/Lookup.hs b/src/GF/Grammar/Lookup.hs
index a4208b21b..b8c6a2a19 100644
--- a/src/GF/Grammar/Lookup.hs
+++ b/src/GF/Grammar/Lookup.hs
@@ -51,7 +51,9 @@ lookupResDef gr m c = liftM fst $ lookupResDefKind gr m c
 -- 0 = oper, 1 = lin, 2 = canonical. v > 0 means: no need to be recomputed
 lookupResDefKind :: SourceGrammar -> Ident -> Ident -> Err (Term,Int)
 lookupResDefKind gr m c 
- | isPredefCat c = return (Q cPredefAbs c,2) --- need this in gf3 12/6/2008 
+ | isPredefCat c = liftM (flip (,) 1) $ lock c defLinType 
+   ---- return (Q cPredefCnc c,2) 
+   ---- was PredefAbs till 3/9/2008, with explanation: need this in gf3 12/6/2008 
  | otherwise = look True m c where 
   look isTop m c = do
     mi   <- lookupModule gr m
diff --git a/src/GF/Grammar/Predef.hs b/src/GF/Grammar/Predef.hs
index 71f152f92..045df06ca 100644
--- a/src/GF/Grammar/Predef.hs
+++ b/src/GF/Grammar/Predef.hs
@@ -15,7 +15,7 @@ module GF.Grammar.Predef
           , cTok
           , cStr
           , cStrs
-          , cPredefAbs, cPredef
+          , cPredefAbs, cPredefCnc, cPredef
           , cInt
           , cFloat
           , cString
@@ -58,6 +58,9 @@ cStrs = identC (BS.pack "Strs")
 cPredefAbs :: Ident
 cPredefAbs = identC (BS.pack "PredefAbs")
 
+cPredefCnc :: Ident
+cPredefCnc = identC (BS.pack "PredefCnc")
+
 cPredef :: Ident
 cPredef = identC (BS.pack "Predef")
 
diff --git a/src/GF/Infra/Modules.hs b/src/GF/Infra/Modules.hs
index 797f729c8..913afc89e 100644
--- a/src/GF/Infra/Modules.hs
+++ b/src/GF/Infra/Modules.hs
@@ -378,6 +378,7 @@ sameMType m n = case (n,m) of
   (MTInterface,  MTInstance _) -> True
   (MTInterface,  MTResource)   -> True    -- for reuse
   (MTInterface,  MTAbstract)   -> True    -- for reuse
+  (MTInterface,  MTConcrete _) -> True    -- for reuse
 
   (MTResource,   MTInstance _) -> True
   (MTResource,   MTConcrete _) -> True    -- for reuse